NATO increases Libyan airstrikes

>>> president obama has received a letter from of all people moammar gadhafi of libya who in a rambling three-page letter in english pleads with him to stop the nato air campaign which he called quote an unjust war against a small people of a developing country. he also wished mr. obama good luck in his upcoming at the same time the anti- gadhafi rebels are continuing to slam nato saying the coalition isn't doing enough to protect them on the ground. nbc's stephanie gosk reports from benghazi tonight.

>> reporter: in a punishing back and forth battle with government loyalists rebel forces say nato is letting them down. "we haven't seen a thing from nato " this man told us. "they're weak. we hear the planes but they don't hit anything." when nato took control of the operation the number of air strikes dropped. rebels here in eastern libya say that was enough time for moammar gadhafi to regroup and rearm. today nato responded, increasing the number of air strikes from 130 to 200. but in libya 's western town of misrata, nato commanders say gadhafi loyalists are using civilians as human shields , and they worry air attacks will kill innocent people.

>> there's a limit, physical limit because we are not allowed boots on the ground , there is a limit to what we're able to do in that respect.

>> reporter: nato 's mandate from the u.n. is to protect civilian populations, but the rebels in eastern libya want more than protection. they want coordinated military assistance. without it they stand little chance against gadhafi 's superior firepower. every day a group of ambulances line up just off the front line waiting to ferry the injured back to hospitals. do you think the rebels need more support than what they're getting?

>> i think the rebels need more organization more than support. you know? they need weapons, i know that. but they need more organization.

>> reporter: some things have improved. the supply lines of food and water run smoothly, and movements to the front appear better controlled. this convoy armed with old makeshift russian rockets waited for word from the front before it raced off. but better organization will not make up for lack of firepower, and for now these fighters don't have it. u.s. military officials tell nbc news that gadhafi 's repositioning his troops right now for a move east in the coming days. they pose a direct threat to the city of ajdabiya with an eye of attacking rebels here.

>> stephanie gosk on post tonight.